The 9 Abdominal Regions & the 4 Abdominal Quadrants

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    The thoracic region is surrounded by bone: 12 pairs of ribs, a 3-part sternum, and 12 thoracic vertebrae.  A quick reference to the sternum or the nearest rib will guide us very easily when discussing thoracic injuries.  In the case of abdominal injuries, given the wide range of organs in each area, the directional terms we have learned so far do not give us enough detail.  As such, there are two simple ways to divide the abdomen: 4 quadrants (You expected more, maybe?), and 9 regions.

    The 4 abdominal quadrants have very easy lines to remember.  One line is vertical, and it is on the midline, which divides the abdomen into left and right (Don't forget: it's the victim's left or right!).  The other line, which divided the abdomen into upper (superior) and lower (inferior), intersects the midline at a visible landmark.  Can you guess it?  The belly button, or navel, of course.  From here onwards, however, we will no longer be using those words.  The "belly button" is actually called the umbilicus . . . makes sense, doesn't it!
    As for naming each of the four, that's really easy.  Each quadrant has 3 words in the name: Left or Right  Upper or Lower  Quadrant.  For ease in labeling, we give a three letter abbreviation for each: Left Upper Quadrant (LUQ), Left Lower Quadrant (LLQ), Right Upper Quadrant (RUQ), and Right Lower Quadrant (RLQ).
    The 9 abdominal regions take a bit more time to name.  I'm sure, however, that you can find the Umbilical region . . . around the umbilicus, of course!  The areas above and below are given terms relative to the stomach (or at least where people think the stomach is: Epigastric (Epi = above, gastric = stomach), and Hypogastric (Hypo = below, gastric = stomach).  The six remaining regions are divided into left and right (the victim's!), so there are only three more names to learn.  The regions on either side are named according to the area of the spine (the lumbar region is the lower back): Left Lumbar and Right Lumbar.  The regions on either side of the Hypogastric are named according to the bone that makes up the crest of the pelvis (The Iliac crest): Left Iliac and Right Iliac.  Lastly, the two regions on either side of the Epigastric are named according to the organs' placement below the cartilage (chondro =  cartilage) attaching the ribs to the sternum (costal cartilage, costal = ribs).  Since these organs are under the cartilage, their names should make sense: Left Hypochondriac and Right Hypochondriac (no relation to that family member who always complains of being sick!*).

Using the terms above (in bold), label the images below.
Note that the location of the pelvic bones and the costal cartilage has been shown to help guide you.


Click HERE for the Solution!

    Later in the semester we will be looking in detail at the location of certain organs, so that knowing the location of an injury can help you to determine the cause of death (through determining the organs damaged!).

* So why do they call hypochondriacs hypochondriacs?  From the Online Etymology Dictionary
    ( ) :

1839, "illness without a specific cause," earlier (1668) "depression or melancholy without real cause," earlier still (1373) ypocandria "upper abdomen," from L.L. hypochondria "the abdomen," from Gk. hypochondria (neut. pl.), from hypo- "under" + chondros "cartilage" (of the breastbone). Reflecting ancient belief that the viscera of the hypochondria were the seat of melancholy. Hypochondriac (n.) in modern sense first recorded 1888.